In providing light for a medical instrument, such as a headlight for use during surgery, it is very important that the supply of light not be interrupted for any substantial length of time In order to accomplish this function, it is necessary that the lamp emitting the light be free of conditions that can cause lamp failure. At the same time, provision must be made that a replacement lamp can be moved quickly into place and be immediately operative. Apparatus of this type have, in the past, been subject to erratic operation because of accidental blockage of the cooling system and because of the time required to replace a burned-out lamp. Additionally, prior art lamp sources have been difficult to move from place-to-place, due to the housing, and lamp being too hot to handle. These problems have been particularly troublesome in the tense atmosphere of the operating room. Furthermore, lamps cannot be changed by operating room personnel, because they need to remain "sterile" during the operating procedure. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the present invention to provide a light source providing for rapid replacement of an inoperative lamp.
Another object of the invention is to provide a light source having a self-operating shutter for a light-emitting aperture.
A further object of the invention is to provide a light source using dual lamps that can be readily used interchangeably.
Another object of the invention is to provide a light source having an effective cooling system whose air entrance and exit openings are protected against blockage.
A further object of the invention is to provide a light source having handles that remain cool even when the housing is very warm.
Another object of the invention is to provide a light source that is simple and rugged in construction, which is relatively inexpensive to manufacture, and which is capable of a long life of useful service with a minimum of maintenance.